A geologist looking for uranium discovered a giant patella bone here in 1976, and the palaeontologists who were called to investigate then unearthed a fossilised 15m-long herbivore. It was later named Phuwiangosaurus sirindhornae, after Princess Sirindhorn. Dinosaur fever followed (explaining the myriad model dinosaurs in Khon Kaen city), more remains were uncovered and Phu Wiang National Park (อุทยานแห่งชาติภูเวียง) was born.
The park covers a strange horseshoe-shaped mountain that has just a single pass to its interior. Wiang Kao, the district inside the mountain, is a fruit-growing area and is a good place to explore by car if you want to look at traditional village life.